Valve: Virtual Reality requires unfeasibly low latency

According to Valve engineer Michael Abrash, virtual reality gaming is up against a serious hardware limitation, and need a breakthrough moment before it can ever come into its own.

In a lengthy post on the Valve blog, Abrash explained that current hardware latency – the time it takes for what your device is doing to be displayed – is a massive stumbling block.

“Games generally have latency from mouse movement to screen update of 50 ms or higher (sometimes much higher), although I’ve seen numbers as low as about 30 ms for graphically simple games running with tearing (that is, with vsync off). In contrast, I can tell you from personal experience that more than 20 ms is too much for VR and especially AR, but research indicates that 15 ms might be the threshold, or even 7 ms,” he said.

Abrash goes into detail as to why hardware and software engineers are as yet unable to improve latency beyond its current levels, concluding that virtual reality must wait on technological advances.

“There is no way to get low enough display latency out of existing hardware that also has high enough resolution, low enough cost, appropriate image size, compact enough form factor and low enough weight, and suitable pixel quality for consumer-scale AR/VR,” he claimed.

“Someone has to step up and change the hardware rules to bring display latency down. It’s eminently doable, and it will happen – the question is when, and by whom. It’s my hope that if the VR market takes off in the wake of the [Oculus] Rift’s launch, the day when display latency comes down will be near at hand.”

Valve’s hardware teams are said to be looking at VR tech and working on wearable computing devices in addition to other top-secret projects, making a final note of Abrash’s blog – a call for clever VR fans to join the fun – all the more compelling.